“They were many, and all of them carried guns. They came in two vehicles painted in army color. They started shooting in our village,” Lazarus Musa, a resident of Warabe, where the attack happened, said, according to Reuters.

Police said the girls were taken on trucks, along with livestock and food. Boko Haram kidnapped more than 200 girls from a Nigerian school on April 14.

A 16-year-old Nigerian girl who was present during the kidnapping recalls the students were at first happy to see gunmen.

The girls in the school dorm could hear the sound of gunshots from a nearby town. So when armed men in uniforms burst in and promised to rescue them, at first they were relieved.

What they knew was chilling: The men were not government soldiers at all. They were members of the ruthless Islamic extremist group called Boko Haram. They kidnapped the entire group of girls and drove them away in pickup trucks into the dense forest.

Three weeks later, 276 girls are still missing. At least two have died of snakebite, and about 20 others are ill, according to an intermediary who is in touch with their captors.

Their plight — and the failure of the Nigerian military to find them — has drawn international attention to an escalating Islamic extremist insurrection that has killed more than 1,500 so far this year. Boko Haram, the name means “Western education is sinful,” has claimed responsibility for the mass kidnapping and threatened to sell the girls. The claim was made in a video seen Monday.

In the video, Boko Haram leader Abubakar Shekau claimed responsibility for the April 15 kidnappings for the first time. He also threatened to attack more schools and take additional girls.